Take-off control and method



March 1l, 1941.

R. H. FLEET ETAL TAKE-OFF CONTROL AD METHOD 'Qrignal Filed April 24,1.937 4 Sheets-Sheet 1 R. H. FLEET EI'AL TAKE-DFE1 CONTROL AND METHODMarch 11,1941.

Original Filed April 24', 1937 4 Sheets-Sheet 3 fraai/v. fir,

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TAKE-OFF CONTROL AND METHOD Original Filed April 24, 1937 4 Sheets-Sheet2 3 wu om 15e-uam #fle-Er,

MOOOMO 3H, y M. maant-:T Oni-,OL .25mm-51 TMm-OW CONTROL Mm METHODOriginal Filasc April 24, 1937 L Sheds-Sheet 4 y Cna/Mae l" Mar. 11,1941 y aesmsi TAKE-our courant aan rincon Reuben H. Fleet, Williameailey, and isaac M. Haddon, San Diego. welll..

Renewed July lili, will Application April 24 193'?. @criul No.. lttliClaims.

@or invention relates to the launching oi airplaneo, and moreparticularly tothe launching oi' airplanes from moving vehicles.

'll'his application is an improvement upon our y.' copending applicationSerial No. 1051310, illed @woher-14,1936;

Heretol'ore there have been no efllcient means 4 ci control oi takeoffof an airplanen otherthan the skill of the pilot. l

@tten a heavily laden plane will travel down a field, without rising inthe air, a distance greater than it should travel before the brakes areapplied. `This mistake in judgment on the part of the pilot oftenresults in accidents. lli @ne object oi the invention is to Provide anautomatic means for preventing takeofl after a certain distance of runii ample air speed has not been attained at a certain predeterminedpoint in the run.

Another objectof the invention is to provide air speed control forreleasing an airplane from `avelriicle on which it is mounted forlaunching.

i Still another object of the invention is to pro;

vide an electrical circuit which controls the release oi' an airplanefrom a launching vehicle.

Yet another object ot the invention is to provide anl automatic meansfor applying the brakes ou a vehicle carrying an airplane forlaunching Yat a certain point in its run.

au 'A further object of the inventionis to provide a'y novel form ofhold-back mechanism by which the airplane is fastened at a point at thebegin ning oi' its run while the motors are beine:

. warmed up.

`35 still further object lof the invention isO provide lan air pressureswitch for controlling thqyoperating mechanism, such control'dependingonthe air speed forA which the device is set.

Aliet a further object of the invention is to n` provide novel hold-downmembersby which anV airplane is held to a launching vehicle.

' Still'a iurthercblect of the invention, is to providemeans for holdingdown the nose oi' an airplane during the takeoi! run until the proper wair speed is reached for the airplane totake oil from the vehicle.

Another object of the invention-lato permit 1 the launching oialrplanes'without human atl tention, or atleast Withoutskilled'handll'ngdur- ,oo lng the takeout run until after thevplaneleaves .the vehicle. In lthisv connection the completely automatictakeoi! is y'especially valuable for flights controlled by robotpilotaf'yj l f With` these and other objects'fin view,"'which as may beincident to our' improvements, the in- (Ci. 2Mb-till veution consists inthe parte and combinations to be hereinafter set iorth and claimed, withthe understanding that the several neeessaryelements comprlsinirourinvention maybe varied in construction. proportions and arrangement,without departing from the spirit and scope oi.' the appended claims.

In order to make our invention more clearly understood. we have shown inthe accompanying drawings means ior carrying the same into praclo ticaleilect without limiting the improvements in their useful applications tothepartlcular constructions which, i'crthe purpose of explanation, havebeen made the subjectl of illustration.

In the drawings: x5

Figure l is a diagrammatic view of a system employing my invention. A

Figure 2 is a view in side elevation of a seaplane mounted on mysupporting vehicle, part of the supporting vehicle being broken away to2o show the construction; j

Figure 3 is a view in iront elevation of a sea' plane mounted on thesupporting platform of the vehicle, showing the hold-down means by whichthe seaplane is held attached to the vehicle with 25 its nose down. l y

Figure 4 is a detail view partly in section of the holding means for theseaplane.

Figure 5 is a detail sectional view showing the holding means removedfrom its socket in the ao wall oi the seaplane. r

Figure 6 is a view taken along the line I-B of Figure 4.

Figure 'I is a view taken along lthe line 1 1 of Figure 4.

i Figure 81s a diagrammatic view o! the control circuit for releasingthe seaplane from the supporting vehicle.'

Figure 9 is a sectional view taken through our control switch operatedby air speed. 40

Figure 10 is aldetail perspective view of the control for 'the brakemechanism.

Figure l1 is a sectional view taken through our three-way control valvecontrolling the air to the brakes.

Figure l2 is a detail view partly in section of the attachment for thehold-back device whereby the airplane is attached to the hold-backcable.

In our `system the airplane is held on the sup- .'porting vehicle withits. nose held down, so thatoo the airplane is in a substantiallyrio-lift attitude.

' The elevators may be set to raise the nose oi the airplane. Theairplane is held at the end of the track- 'which supports the launchingvehicle by means ci' a cable.

,5 brake cylinders 209.

f ||9 contacts an insulating member |20 which is attached at |2| to theilexible metallic strip 72. Attached by screws |22 to the outside of thehalf |0| of the airtight casing 65 is a support spider |23 which isscrew threaded at |24 to receive a screw threaded. section |25 o f therod i |9 which has a knurled adjusting head |21. A lo'ck nut |28 on thescrew |26 is/ adapted to hold the rod H6 in a desired adjusted positionso as to increase or decrease the distance between contacts 1| and 'I0to adjust the device for varying desired air speeds.

Pipe 68 from the air pressure tube 6| is adapted to 'be attached to aconnection |30t'o the half |00 of the airtight casing 65, and to aconnection I 3| is adapted to be attached pipe 64 from the Venturi tube60. 4

The functioning of this apparatus has. been previously given inconnection with the descrip- 2 non of the circuit `(Figure ai. It isobvious that,

by adjusting the position of the rod H9, the device may be set forvarying air speeds.

The method of applying the brakes on the vehicle at a certainpredetermined point in the 5 run will now be described. Referringbriefly to Figure 1, it has been explained that at point l the brakesare applied on the vehicle.' In Figure 2 and Figures 10 and 1l is shownthe mech- |30 anism for applying the brakes on the vehicle.

There is provided an air tank 200 which is adapted to receive air underpressure from inlet pipe having a one-way filling valve 202. The pipe20| communicates with a pipe 203. There is 35 a shut-off valve 204provided in the pipe 203. Air under pressure can be'sent in to thevtank200 through valve 202. Connected-to pipe 203 is a pipe 203 whichcommunicates with an operating valve which is indicated generally by thenumeral n 205. The operating valve also communicates to the brakecylinders.

The brake cylinders are located at either end of the vehicle 3 and areconnected to the pipe 45201 through pipe 208. The brake cylinders Wehave indicated in Figure 2 by the numeral 209.

Through suitable operating linkage connections indicated generally bythe numeral 2 I0 the brake shoes 2|| may be applied on admitting air tothe The details of this construction are shown in our copendingapplication Serial No. 112,803, filed November 25, 1936, and it is notthought necessary to repeat the detailed description therein contained.

55 The valve 205 comprises a valve casing 2I2 and member 2I3 is aconnecting shaft 2|`| whichv is :60 provided with a crank 2|8 and acontact member 2I9.

' The contact member 2|9 is adapted to strike a trip 220 set in asupporting base 22|. The trip 220 is located at the point designated bynumeral 05 'l in Figure l. As the vehicle passes the station the trip220 strikes contact member 2|9 and rotates the rotatable member 2 I3 ofthe valve.

With the parts shown in the position indicated in solid lines in Figurel1, the brakes ex- '[0` haust through ducts 2|4 and 2|6. With the partsshown in the position indicated in dotted Vlines in Figure 1l, airpasses from the container 200 through duct 2|5 and duct 2|6 to pipe 206,thence to pipe 201 and thence to brake cylinders 209 7l to apply thebrakes.

through a, pipe 206 with a pipe 201 which goes we have provided cableengaging members 223 at eitherl end of the vehicle 3. 'Ihese memberscomprise a throat construction 224 in which the cable 0 is adapted to beguided, and a pivoted catch 225 which is pushed aside by the cable B asit yl5 enters the throat 224 and which falls in position behind thecable'after the cable has once passed into the throat 224. Thus, if thebrakes have not stopped the vehicle, which may or may not support theairplane at this point in the run. de--20 pending upon whether or notthe airplane has taken off from the launching vehicle, the vehicle willbe arrested by the arresting cable 8 at the end of the run.

The details for applyingl brakes to the arrest- 25 ing cable are wellknown, and it is not believed necessary to describe them. Details of oneform of arresting cable construction are shown in our copendingapplication Serial No. 105,611, led October 14, 1936. i v

The hold-down mechanism for holding the airplane'in the beginning of therun will now be described. Referring to Figure 1, we have shown thatthere is a cable 5 which holds the airplane at the beginning of the rununtil the motors are,35

running full throttle, at which time the pilot releases the cable 5 fromthe airplane, and the airplane and the launching vehicle, preferablyonly under the power of the motive power plant of the airplane, proceeddown the rail track 4. ,4o 'I'he cable 5 is attached to an anchor member'300 which may be mounted between the rails of the rail track 4. Thecable 5 has a loop 30| which is adapted to pass through an aperture 302in a male member 303 which is adapted to slide in a slideway 304 formedin a support member 305 which fits within an aperture 306 formed in thebottom 301 of the fuselage. 'I'he aperture 306 is braced by means of abracing member 308 which acts as asupport for the strain imposed byforces acting through the support member 305.

Pivoted on the support member 305 on a pivot 309 is a fastener 3|0. Thefastener 3|0 is provided with a catch 3|| having a sloping surface 3|2which is adapted to engage a sloping surface "i 3|3 formed on the end ofthe male member 303.

A coil spring 3 I4 is adapted to urge the fastener 3| 0 in the up, 0rdisengaging, position. The slope of the surfaces 3|2 and 3|3 is such asto tend to move the fastener 3|0 in the up, or disengaged, 60 p osition.In order to hold the fastener 3|0 in the down, or engaging, position,there is provided a release member 3I5 which is pivoted on a. pivot 3|6supported by the socket 305. One arm 3|'| of the release member 3I5 isadapted to bear G5 against the top of the fastener 3|0.

The other arm 3|8 of the release member 3|5 is held in the positionindicated in solid lines in Figure 12 by means of a spring 3|9 which isattached to the arm 3|8 and to the fuselage 301. 70

A cable 320 is pivotally attached at 32| through a suitable connection322 to the arm 3|8 of the release member 3I5.

A stop 323 prevents the spring 3|9 from mov\ ing the release memberbeyond the position piane at a point forward of the center of gravity ofthe airplane, a pivoted member on each arm adapted to tit within anaperture provided in each side of the p iane so as to maintain theairplane in a substantially 11o-lift attitude, and means actuated by theair speed to release the arms from the airplane.

B. A hold down mechanism for holding an airplane to a. launching vehiclecomprising a pair of 10 arms carried by the vehicle, a. pivoted elementon each arm adapted to t in an aperture provided on each side of thenose of the airplane, an electricaily operated trip for each pivotedelement for moving the pivoted element to release the arms from theairplane, and means operated by the air speed to actuate theelectrically operated trip. l

REUBEN H. FLEET.

WILLIAM B. WHEATLEY.

ISAAC M. LADDON.

